Good inexpensive power supply for 3 cards?

[toben]

Hello,

I need a good and not terribly expensive PSU for 2x R9 270 and 1x 78750.

My current 500w PSU will not do even 2 of the 270's.
http://www.amazon.com/gp/product/B001G0WPLK/ref=oh_details_o09_s00_i01?ie=UTF8&psc=1

In theory it should power all 3 but I cant figure out the rails argument. Let me know if you have a solution.

Thanks in advance!

[InCoinsITrust]

Try to use good 850W unit with one power line, like corsair PSU's.

[kcobra]

Yes, a quality 850w psu will power two 270's and one 78XX just fine. Heck, I've got 3 7870's running on a 650w XFX unit without issue (no overclocking though). Newegg has the XFX 850w non-modular bronze unit for $100 AR.

[InCoinsITrust]

Lets remember that psu best efficiency is at 60-70% load, and it will live longer if loaded at that percentage.